> Ahh PCI ata controller, that's the difference.  I'm using the mobo
> controllers.  No DMA on the PCI bus would theoretically take double the
> CPU time (once to handle the ata traffic and again to handle the pci
> traffic) the way I understand it (albeit not very well :) )

Yes, but I disabled DMA when the drive was on the onboard controller.
I then also tried the PCI controller to see how that faired, with DMA
enabled. Basically DMA just lets programs/devices talk without using
CPU power, which is why with DMA enabled you can stream a mpg file
from the hard drive to the pvr-x50 with almost NO cpu usage. If you
have DMA disabled on the HD, then the CPU cycles are uses to move that
data across the bus from one device to another... Either way, my
fairly obvious problem with the secondary IDE controller is that it's
on the exact same bus as the pvr card, so they have to share all the
buss bandwidth the machine has, which is probably 66Mhz on mine as
well.
 
> Since you are willing to build a new one, I saw someone mention
> somewhere that most if not all VIA and Intel mobo chipsets are
> supported. YMMV.   If you get in the 1.8GZ range this problem should
> disappear from what I've been told.  Get one of those new fangled 800mzh
> intel bus things :) it should work like a dream.

Hehe, this was a project a friend and I said "Hey, it would be cool if
we beet the TiVo man and built some free PVR's out of stuff we have
lying around. All we need is $180 pvr cards!" This is now a $500
project, but I'm "willing" to drop the money on new (inexpensive)
hardware, mainly because I've used MythTV enough to see how cool it
is. It was working ok for me for about a week, so I got real used to
watching recordings without commercials and it made me drool!

> Overall, what I've seen about our problem, the bus speed seems to be the
> limiting factor.  CPU isn't the problem.  I think my bus is running at
> 66mzh.  Probably anything you can buy now will make a difference
>  I saw a descent barebones on tigerdirect.com for about $200 a while
> back.  I don't see it now but I had to dig a bit before and I'm out of
> time.  If I run across it again Ill let you know

While I agree the bus is a limiting factor, I just don't want to buy a
1.5-2Ghz cpu, board, ram, case, and find out it still doesn't work any
better. That's why I'm pressed to find someone with a *working* MythTV
setup and a PVR-350 with Tuner type = 47. I priced out some decent
stuff for under $200, using the PVR and HD I have. Nice new pvr-ish
case too.

As for bus speed, I think PCI is still clocked at 66Mhz. That was the
big advantage of AGP, it's a much faster bus and can make use of the
faster bus on the boards themselves, and provides some other
advantages like share memory with the system, rather than built on to
the card, if you can call that an advantage.

-Kenneth


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